1. Field of the Invention
The present invention relates to carbon canisters, which are used onboard automotive vehicles for collecting hydrocarbon vapors emanating from vehicular fuel systems.
2. Background of the Invention
As is known in the art, modern vehicles are equipped with fuel vapor recovery systems for collecting vapors discharged from a liquid fuel tank onboard the vehicle. Fuel vapors exist in the fuel tank above the liquid fuel. During vehicle refueling, fuel vapors are displaced by liquid fuel entering the fuel tank. The fuel vapor recovery system collects these displaced fuel vapors in a carbon canister mounted, typically, in the engine compartment under the hood.
The fuel vapors absorb onto the surfaces of carbon particles within the carbon canister. When changing from a vapor state to an absorbed state in the canister, the fuel liberates energy causing the temperature in the carbon canister, and hence the temperature of the carbon in such canister to rise. Unfortunately, as the temperature of the carbon in the canister increases, the effectiveness of the carbon-in absorbing the fuel vapors is reduced.